High temperature transformations of the Au7Cu5Al4 shape-memory alloy
The beta-phase of Au7Cu5Al4 undergoes a reversible shape-memory phase transformation, however there has been some uncertainty regarding the crystal structure or structures of the parent phase. Here we show that, under equilibrium conditions, the parent phase possesses the L21 structure between its A...
| Main Authors: | , , , , , |
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| Format: | Journal Article |
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Elsevier B.V.
2011
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| Online Access: | http://hdl.handle.net/20.500.11937/8871 |
| _version_ | 1848745785281216512 |
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| author | Cortie, M. Kealley, Cat Bhatia, V. Thorogood, G. Elcombe, M. Avdeev, M. |
| author_facet | Cortie, M. Kealley, Cat Bhatia, V. Thorogood, G. Elcombe, M. Avdeev, M. |
| author_sort | Cortie, M. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The beta-phase of Au7Cu5Al4 undergoes a reversible shape-memory phase transformation, however there has been some uncertainty regarding the crystal structure or structures of the parent phase. Here we show that, under equilibrium conditions, the parent phase possesses the L21 structure between its Ap (about 79 degrees C) and ~630 degrees C, and the B2 primitive cubic structure between ~630 degrees C and its melting point. It melts directly from B2 into the liquid state and hence never achieves the random bcc A2 structure that has been previously mooted. Splat-cast samples of the alloy are martensitic, proving that development of equilibrium order and defect concentration are not pre-requisites for the A->M transformation to occur |
| first_indexed | 2025-11-14T06:22:52Z |
| format | Journal Article |
| id | curtin-20.500.11937-8871 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T06:22:52Z |
| publishDate | 2011 |
| publisher | Elsevier B.V. |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-88712017-02-28T01:31:01Z High temperature transformations of the Au7Cu5Al4 shape-memory alloy Cortie, M. Kealley, Cat Bhatia, V. Thorogood, G. Elcombe, M. Avdeev, M. Shape memory Crystal structure - - - Intermetallic - Crystal structure Intermetallic X-ray diffraction Order-disorder effect The beta-phase of Au7Cu5Al4 undergoes a reversible shape-memory phase transformation, however there has been some uncertainty regarding the crystal structure or structures of the parent phase. Here we show that, under equilibrium conditions, the parent phase possesses the L21 structure between its Ap (about 79 degrees C) and ~630 degrees C, and the B2 primitive cubic structure between ~630 degrees C and its melting point. It melts directly from B2 into the liquid state and hence never achieves the random bcc A2 structure that has been previously mooted. Splat-cast samples of the alloy are martensitic, proving that development of equilibrium order and defect concentration are not pre-requisites for the A->M transformation to occur 2011 Journal Article http://hdl.handle.net/20.500.11937/8871 Elsevier B.V. restricted |
| spellingShingle | Shape memory Crystal structure - - - Intermetallic - Crystal structure Intermetallic X-ray diffraction Order-disorder effect Cortie, M. Kealley, Cat Bhatia, V. Thorogood, G. Elcombe, M. Avdeev, M. High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title | High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title_full | High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title_fullStr | High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title_full_unstemmed | High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title_short | High temperature transformations of the Au7Cu5Al4 shape-memory alloy |
| title_sort | high temperature transformations of the au7cu5al4 shape-memory alloy |
| topic | Shape memory Crystal structure - - - Intermetallic - Crystal structure Intermetallic X-ray diffraction Order-disorder effect |
| url | http://hdl.handle.net/20.500.11937/8871 |